The use of drugs for acne´s treatment is ever more common, emphasizing the efficacy of the drug Roaccutane®, a retinoid which contains a substance in its formula derivative of vitamin A, the isotretinoin (13-cis-retinoic acid), which improves the clinical aspects of severe acne and it is associated with the activity suppression and decreasing of the sebaceous gland size. Several studies demonstrate that Roaccutane® is teratogenic during its use or even up to a month after its discontinuation, but reports in that literature which proving its toxicity to the male reproductive system are rare and inconclusive. This study investigated the toxic action of the drug on adult Wistar rat testicular morphophysiology. Twenty-four adult rats were divided into three groups: two treated groups and one control group. The animals of the treated group were submitted with gavage administration of 0,2mg and 0,4mg of Roaccutane® in 1,0 mL of soybean oil respectively, once a day, for 60 days. The animals in the control group also were treated with gavage administration of 1,0 mL of water/animal/day. The animals were euthanized 60 days after the first exposure, it was being made biometrics analyzes of the body and reproductive organs, and testicular stereology and morphometry, sperm evaluation and serum testosterone measurement. Therapeutic doses of Roaccutane® showed little interference on the seminiferous tubules, requiring analysis of the cell population to obtain details of the action of this drug in this compartment. However, treatment with Roaccutane® at both doses caused an increase in tubular compartment and reducing the intertubular compartment, the percentage of macrophages, the number of Leydig cells and hence reduced plasma testosterone levels and prostate weight. According to the evaluation of the drug on sperm viability there was damage in the integrity of the sperm membrane accompanied by low sperm motility total. The administration of this drug should be careful since it seemed to exert toxic effects affecting a testicular endocrine portion.